Legal Question in Landlord & Tenant Law in Massachusetts

Why tell your landlord at all?

If you DO tell him, chances are he cannot discriminate against you legally. [There are some exceptions to this for owner occupants, etc.]

However, just because something is illegal, doesn't mean it doesn't happen. If you have no obligation to alert him to your pregnancy, and normally you would not, don't say anything. If he retaliates against you now or in the future due to your pregnancy, contact the MCAD right away for help. http://www.mass.gov/mcad/

Discrimination on the basis of your pregnancy is probably unlawful in your situation. You do want to make sure that you have the apartment tested and, if necessary, de-leaded. There are rules about how to go about this and who is responsible, and you may want to have an attorney advising you through this process.